U.S. patent number 10,212,801 [Application Number 15/948,047] was granted by the patent office on 2019-02-19 for motor driving device.
This patent grant is currently assigned to FANUC CORPORATION. The grantee listed for this patent is FANUC CORPORATION. Invention is credited to Naoki Masuda, Ryou Matsuda, Shinichi Mizukami.
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United States Patent |
10,212,801 |
Matsuda , et al. |
February 19, 2019 |
Motor driving device
Abstract
A motor driving device is equipped with a narrow pitch component
group made up from a plurality of narrow pitch components having a
plurality of terminals, and in which an interval between the
plurality of terminals is less than or equal to a predetermined
distance, a heat generating component group made up from a
plurality of heat generating components, which are components other
than the narrow pitch components, and which generate heat greater
than or equal to a predetermined amount, a fan configured to blow
wind onto the heat generating component group in order to cool the
heat generating component group, and a printed board on which the
narrow pitch component group is mounted in a manner so that wind is
not blown onto the narrow pitch component group by the fan.
Inventors: |
Matsuda; Ryou (Yamanashi-ken,
JP), Mizukami; Shinichi (Yamanashi-ken,
JP), Masuda; Naoki (Yamanashi-ken, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
FANUC CORPORATION |
Yamanashi |
N/A |
JP |
|
|
Assignee: |
FANUC CORPORATION (Yamanashi,
JP)
|
Family
ID: |
63710490 |
Appl.
No.: |
15/948,047 |
Filed: |
April 9, 2018 |
Prior Publication Data
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|
|
Document
Identifier |
Publication Date |
|
US 20180295709 A1 |
Oct 11, 2018 |
|
Foreign Application Priority Data
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|
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Apr 10, 2017 [JP] |
|
|
2017-077498 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H05K
7/20145 (20130101); H05K 7/20154 (20130101); H05K
7/20909 (20130101); H05K 1/0201 (20130101); H05K
1/0203 (20130101); F28F 13/02 (20130101) |
Current International
Class: |
H05K
1/02 (20060101); H05K 7/20 (20060101); F28F
13/02 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
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63220600 |
|
Sep 1988 |
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JP |
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2007165793 |
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Jun 2007 |
|
JP |
|
20164891 |
|
Jan 2016 |
|
JP |
|
Other References
English Abstract and Machine Translation for Japanese Publication
No. 2016004891 A, published Jan. 12, 2016, 1 pg. cited by applicant
.
English Abstract and Machine Translation for Japanese Publication
No. 2007-165793 A, published Jun. 28, 2007, 9 pgs. cited by
applicant .
English Abstract and Machine Translation for Japanese Publication
No. JPS63220600 A, published Sep. 13, 1988, 6 pgs. cited by
applicant.
|
Primary Examiner: Wilson; Adrian S
Attorney, Agent or Firm: Fredrikson & Byron, P.A.
Claims
What is claimed is:
1. A motor driving device comprising: a narrow pitch component
group made up from a plurality of narrow pitch components having a
plurality of terminals, and in which an interval between the
plurality of terminals is less than or equal to a predetermined
distance; a heat generating component group made up from a
plurality of heat generating components, which are components other
than the narrow pitch components, and which are configured to
generate heat greater than or equal to a predetermined amount; a
fan configured to blow wind onto the heat generating component
group in order to cool the heat generating component group; and a
printed board on which the narrow pitch component group is mounted
in a manner so that wind is not blown onto the narrow pitch
component group by the fan.
2. The motor driving device according to claim 1, wherein: the
narrow pitch component group is mounted on one surface of the
printed board; and the heat generating component group and the fan
are disposed on a side on an opposite surface of the printed board
from the one surface.
3. The motor driving device according to claim 2, wherein the heat
generating component group is arranged while being separated at a
predetermined distance from the printed board.
4. The motor driving device according to claim 1, further
comprising a guiding member configured to block the wind blown from
the fan from flowing to the narrow pitch component group, and to
guide the wind blown from the fan toward the heat generating
component group.
5. The motor driving device according to claim 1, wherein: the
narrow pitch component group is arranged at one end side in a
predetermined direction of the printed board; the heat generating
component group is arranged at another end side in the
predetermined direction of the printed board; as viewed in plan, a
first region in which the narrow pitch component group is arranged,
and a second region in which the heat generating component group is
arranged, are separated from each other by a predetermined interval
along the predetermined direction; and as viewed in plan, the fan
is configured to blow the wind in a direction perpendicular to the
predetermined direction, and thereby to cool the heat generating
component group.
6. The motor driving device according to claim 1, wherein: the
motor driving device is configured to drive motors of each of
respective axes; and the narrow pitch component group, the heat
generating component group, and the fan are provided for each of
the motors of the respective axes.
Description
CROSS-REFERENCE TO RELATED APPLICATION
This application is based upon and claims the benefit of priority
from Japanese Patent Application No. 2017-077498 filed on Apr. 10,
2017, the contents of which are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a motor driving device for driving
a motor.
Description of the Related Art
In Japanese Laid-Open Patent Publication No. 2016-004891, a cooling
device is disclosed. According to Japanese Laid-Open Patent
Publication No. 2016-004891, in the case that the cooling device is
disposed in a control panel in an environment in which a cutting
fluid mist exists, in order to prevent electronic components from
breaking down or malfunctioning due to wind that includes the
cutting fluid mist therein and which is blown from the cooling
device, it is disclosed to provide a mist collecting member in the
cooling device to capture and collect the mist.
SUMMARY OF THE INVENTION
However, in Japanese Laid-Open Patent Publication No. 2016-004891,
the structure of the cooling device is complicated.
Thus, the present invention has the object of providing a motor
driving device, which with a simple configuration, is capable of
preventing malfunctioning or failure of electronic components while
heat generating components in the motor driving device are
cooled.
An aspect of the present invention is characterized by a motor
driving device comprising a narrow pitch component group made up
from a plurality of narrow pitch components having a plurality of
terminals, and in which an interval between the plurality of
terminals is less than or equal to a predetermined distance, a heat
generating component group made up from a plurality of heat
generating components, which are components other than the narrow
pitch components, and which are configured to generate heat greater
than or equal to a predetermined amount, a fan configured to blow
wind onto the heat generating component group in order to cool the
heat generating component group, and a printed board on which the
narrow pitch component group is mounted in a manner so that wind is
not blown onto the narrow pitch component group by the fan.
According to the present invention, with a simple configuration, it
is possible to prevent the wind blown by the fan from flowing to
the narrow pitch component group, while also cooling the heat
generating components by the wind blown from the fan. Accordingly,
it is possible to prevent the narrow pitch components from
malfunctioning due to atomized liquid contained within the wind
blown by the fan.
The above and other objects, features, and advantages of the
present invention will become more apparent from the following
description when taken in conjunction with the accompanying
drawings, in which preferred embodiments of the present invention
are shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view showing an exemplary schematic configuration
of a motor driving device according to a first embodiment of the
present invention;
FIG. 2 is a diagram showing another example of the motor driving
device shown in FIG. 1;
FIG. 3 is a diagram showing still another example of the motor
driving device shown in FIG. 1;
FIG. 4 is a side view showing an exemplary schematic configuration
of a motor driving device according to a second embodiment of the
present invention;
FIG. 5 is a diagram showing another example of the motor driving
device shown in FIG. 4;
FIG. 6 is a side view showing an exemplary schematic configuration
of a motor driving device according to a third embodiment of the
present invention; and
FIG. 7 is a plan view showing an exemplary schematic configuration
of a motor driving device according to a fourth embodiment of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of a motor driving device according to the
present invention will be presented and described in detail below
with reference to the accompanying drawings.
First Embodiment
FIG. 1 is a side view showing an exemplary schematic configuration
of a motor driving device 10 according to a first embodiment. In
the following description, up, down, left and right directions will
be explained in accordance with the directions of the arrows shown
in FIG. 1. The motor driving device 10 that drives a motor includes
a printed board 12, a narrow pitch component group 14 made up from
a plurality of narrow pitch components, a heat generating component
group 16 made up from a plurality of heat generating components, a
fan 18 configured to blow wind onto the heat generating component
group 16 and cool the heat generating component group 16, and a
housing 20 in which the printed board 12, the narrow pitch
component group 14, the heat generating component group 16, and the
fan 18 are accommodated. The printed board 12, the narrow pitch
component group 14, and the heat generating component group 16 are
elements that serve to drive the motor. Moreover, the wind blown by
the fan 18 includes an atomized liquid (for example, a liquid such
as cutting fluid composed of oil, water, or the like). Hereinafter,
the atomized liquid will be referred to simply as a mist.
As shown in FIG. 2, the fan 18 may be disposed outside of the
housing 20. In the case that the fan 18 is disposed externally of
the housing 20, it is necessary that a ventilation opening 20a be
provided in the housing 20 through which the wind blown by the fan
18 flows into the housing 20.
A heat sink 22 is attached to the motor driving device 10. The heat
sink 22 serves to cool the heat generating component group 16.
Accordingly, the heat sink 22 is disposed on a side of the heat
generating component group 16. Although the heat sink 22 may be
disposed outside of the housing 20, or may also be disposed inside
the housing 20, according to the first embodiment, the heat sink 22
is disposed externally of the housing 20. Moreover, although not
shown, a fan that blows wind onto the heat sink 22 may be
separately provided.
In this instance, the narrow pitch components are components having
a plurality of terminals (not shown), and in which an interval
between the terminals is less than or equal to a predetermined
distance (for example, 2 mm). For example, the narrow pitch
components are ICs (Integrated Circuits) in which a distance
between the terminals is less than or equal to the predetermined
distance. The narrow pitch components are electronic components
that are likely to malfunction due to the mist, and the amount of
heat generated thereby is less than a predetermined amount. Such
malfunctioning or failure is caused, for example, due to
insufficient insulation.
The heat generating components are components other than the narrow
pitch components, and are components that generate heat greater
than or equal to a predetermined amount. The heat generating
components, for example, are components which are provided in order
to supply a large driving current to the motor, and are constituted
by power devices, bus bars, or the like. The power devices are
power semiconductor elements made up of insulated gate bipolar
transistors (IGBT), thyristors, rectifier diodes, or power
transistors (power MOSFET). The heat generating component group 16
may also include intelligent power modules (IPM). The heat
generating components are components which are unlikely to
experience malfunctioning due to the mist.
The narrow pitch component group 14 is mounted on one surface 12a
of the printed board 12, and the heat generating component group 16
is disposed on a surface (opposite surface) 12b side of the printed
board 12 opposite from the one surface 12a. Hereinafter, the one
surface 12a of the printed board 12 on which the narrow pitch
component group 14 is mounted will be referred to as a front
surface (printed surface), and the surface (opposite surface) 12b
on the side where the heat generating component group 16 and the
fan 18 are disposed will be referred to as a rear surface (solder
surface).
The heat generating component group 16 may be supported by the
printed board 12 or may be supported by the housing 20. At this
time, signal lines for outputting command signals from the narrow
pitch components to the heat generating components are electrically
connected to the narrow pitch components and the heat generating
components, however, because the signal lines do not generate heat
that is greater than or equal to a predetermined amount, such
signal lines are not included in either the narrow pitch components
or the heat generating components.
The fan 18 is disposed on the rear surface 12b side of the printed
board 12. In accordance with this feature, it is possible to
prevent the wind that is blown from the fan 18 from flowing to the
narrow pitch component group 14, together with enabling the wind
blown from the fan 18 to flow toward the heat generating component
group 16. Moreover, as shown in FIG. 3, by the printed board 12
being extended to an area above the fan 18, it is possible to
prevent the wind blown from the fan 18 from flowing to the narrow
pitch component group 14, and to guide the wind blown from the fan
18 so as to flow toward the heat generating component group 16. In
this case, a portion 19 of the printed board 12 that extends above
the fan 18 functions as a guiding member.
In this manner, the narrow pitch component group 14 is mounted on
the printed board 12 in a manner so that wind is not blown by the
fan 18 onto the narrow pitch component group 14. More specifically,
the heat generating component group 16 and the fan 18 are disposed
on the rear surface 12b on an opposite side from the front surface
12a of the printed board 12 on which the narrow pitch component
group 14 is mounted. Consequently, it is possible to prevent the
wind (including the mist) blown by the fan 18 from flowing to the
narrow pitch component group 14, and to prevent the narrow pitch
components from breaking down or malfunctioning due to the wind
blown from the fan 18.
Second Embodiment
FIG. 4 is a side view showing an exemplary schematic configuration
of a motor driving device 10 according to a second embodiment.
Components that are the same or similar to those of the first
embodiment are denoted with the same reference numerals, and points
that differ from the first embodiment will be described below. In
the second embodiment as well, the narrow pitch component group 14
is mounted on the printed board 12 in a manner so that wind is not
blown by the fan 18 onto the narrow pitch component group 14.
According to the first embodiment, the fan 18 is disposed on the
rear surface 12b side of the printed board 12. However, in the
second embodiment, the fan 18 may be disposed on the front surface
12a side of the printed board 12. In this case, the wind blown by
the fan 18 would flow disadvantageously onto the narrow pitch
component group 14. Thus, in the second embodiment, the guiding
member 30 is provided in the interior of the housing 20, so as to
block the wind blown from the fan 18 from flowing to the narrow
pitch component group 14, and to guide the wind blown from the fan
18 toward the heat generating component group 16.
Consequently, it is possible to reliably prevent the wind including
the mist blown by the fan 18 from flowing to the narrow pitch
component group 14, and to reliably prevent the narrow pitch
components from breaking down or malfunctioning due to the wind
blown from the fan 18.
Moreover, similar to the case in which the fan 18 is disposed
externally of the housing 20, the guiding member 30 is provided,
which blocks the wind blown from the fan 18 in the interior of the
housing 20 from flowing to the narrow pitch component group 14, and
guides the wind blown from the fan 18 so as to flow toward the heat
generating component group 16. In this case, as shown in FIG. 5,
the guiding member 30 guides the wind, which flows from the
ventilation opening 20a formed in the housing 20, so as to flow
toward the heat generating component group 16.
Further, a configuration may be provided in which the guiding
member 30 is simply disposed in the motor driving device 10
described in the aforementioned first embodiment. In other words,
the guiding member 30 may also be provided in a configuration in
which the fan 18 is disposed on the rear surface 12b side of the
printed board 12. In accordance with this feature, it is possible
to reliably prevent the wind blown by the fan 18 from flowing onto
the narrow pitch component group 14.
Third Embodiment
FIG. 6 is a side view showing an exemplary schematic configuration
of a motor driving device 10 according to a third embodiment.
Components that are the same or similar to those of the first
embodiment are denoted with the same reference numerals, and points
that differ from the first embodiment will be described below. In
the third embodiment as well, the narrow pitch component group 14
is mounted on the printed board 12 in a manner so that wind is not
blown by the fan 18 onto the narrow pitch component group 14.
According to the third embodiment, the heat generating component
group 16 is arranged while being separated at a predetermined
distance from the printed board 12. The heat generating component
group 16 is disposed on the printed board 12 via connecting members
32. The connecting members 32 are interposed between the printed
board 12 and the heat generating component group 16, in order to
set the distance between the printed board 12 and the heat
generating component group 16 at a predetermined distance. Signal
lines for outputting command signals from the narrow pitch
components to the heat generating components may be provided in the
connecting members 32.
In accordance with such a configuration, since the installation
position of the fan 18 can be separated from the printed board 12,
it is possible to prevent the wind (including the mist) that is
blown from the fan 18 from flowing to the narrow pitch component
group 14, together with enabling the wind blown from the fan 18 to
flow toward the heat generating component group 16. Accordingly, it
is possible to reliably prevent the narrow pitch components from
malfunctioning due to the wind blown from the fan 18.
In the example shown in FIG. 6, the printed board 12 and the heat
generating component group 16 are separated by interposing the
connecting members 32 therebetween, however, the connecting members
32 need not necessarily be provided. In this case, the heat
generating component group 16 may be supported by the housing 20.
Thus, in essence, the printed board 12 and the heat generating
component group 16 may be separated by a predetermined
distance.
In the third embodiment as well, the guiding member 30 that was
described in the aforementioned second embodiment may also be
provided. In accordance with this feature, it is possible to
reliably prevent the wind blown by the fan 18 from flowing onto the
narrow pitch component group 14.
Fourth Embodiment
FIG. 7 is a plan view showing an exemplary schematic configuration
of a motor driving device 10 according to a fourth embodiment.
Components that are the same or similar to those of the first
embodiment are denoted with the same reference numerals, and points
that differ from the first embodiment will be described below. In
the fourth embodiment as well, the narrow pitch component group 14
is mounted on the printed board 12 in a manner so that wind is not
blown by the fan 18 onto the narrow pitch component group 14. In
FIG. 7, illustration of the housing 20 and the heat sink 22 is
omitted.
According to the fourth embodiment, the narrow pitch component
group 14 is arranged at one end side (right side) in a
predetermined direction (left/right direction) of the printed board
12, and the heat generating component group 16 is arranged at
another end side (left side) in the predetermined direction
(left/right direction) of the printed board 12. As viewed in plan,
a first region 14a in which the narrow pitch component group 14 is
arranged, and a second region 16a in which the heat generating
component group 16 is arranged are separated from each other by a
predetermined interval along the predetermined direction
(left/right direction). According to the fourth embodiment, the
narrow pitch component group 14 is mounted on the front surface 12a
of the printed board 12, and the heat generating component group 16
is disposed on the front surface 12a side of the printed board
12.
As viewed in plan, the fan 18 blows the wind in a direction
(front/rear direction) perpendicular to the predetermined direction
(left/right direction), and thereby cools the heat generating
component group 16. Therefore, the fan 18 is arranged on the front
side or the rear side of the heat generating component group 16. In
the example shown in FIG. 7, an example is shown in which the fan
18 is installed on the rear side of the heat generating component
group 16.
In accordance with this feature, it is possible to prevent the wind
(including the mist) that is blown by the fan 18 from flowing to
the narrow pitch component group 14, together with enabling the
wind blown from the fan 18 to flow toward the heat generating
component group 16. Accordingly, it is possible to prevent the
narrow pitch components from malfunctioning due to the wind blown
from the fan 18.
Moreover, as was described in relation to the aforementioned first
through third embodiments, the narrow pitch component group 14 may
be mounted on the front surface 12a of the printed board 12, and
the heat generating component group 16 may be disposed on the rear
surface 12b side of the printed board 12. In this case, it is
possible to more effectively prevent the wind blown by the fan 18
from flowing to the narrow pitch component group 14, and to more
effectively prevent the narrow pitch components from breaking down
or malfunctioning due to the wind blown from the fan 18.
Further, in the fourth embodiment as well, the guiding member 30
that was described in the aforementioned second embodiment may also
be provided. In accordance with this feature, it is possible to
reliably prevent the wind blown by the fan 18 from flowing onto the
narrow pitch component group 14. Further, in the fourth embodiment
as well, as described in connection with the aforementioned third
embodiment, the printed board 12 and the heat generating component
group 16 may be arranged while being separated from each other by a
predetermined distance.
[Modifications]
The motor driving device 10 described in each of the respective
embodiments above may be a device configured to drive motors of
each of respective axes (for example, respective axes such as an
X-axis, a Y-axis, and a Z-axis, etc.). In this case, the narrow
pitch component group 14, the heat generating component group 16,
and the fan 18 are provided for each of the motors of the
respective axes.
For example, in the case that the motor driving device 10 is
configured as shown in FIGS. 1 to 6, the narrow pitch component
group 14, the heat generating component group 16, and the fan 18,
which are provided for each of the motors of the respective axes,
may be arranged along the front/rear direction at units of the
axes. Further, in the case that the motor driving device 10 is
configured as shown in FIG. 7, the narrow pitch component group 14,
the heat generating component group 16, and the fan 18, which are
provided for each of the motors of the respective axes, may be
arranged along the left/right direction at units of the axes.
The narrow pitch component group 14, the heat generating component
group 16, and the fan 18, which are provided for each of the motors
of the respective axes, are accommodated inside the housing 20 of
the motor driving device 10. A printed board 12 may be provided for
each of the motors of the respective axes, or a single printed
board 12 may be used in common.
[Technical Concepts Obtained from the Embodiments]
Technical concepts which can be grasped from the above-described
respective embodiments will be described below.
The motor driving device (10) is equipped with the narrow pitch
component group (14) made up from the plurality of narrow pitch
components having a plurality of terminals, and in which an
interval between the plurality of terminals is less than or equal
to a predetermined distance, the heat generating component group
(16) made up from the plurality of heat generating components,
which are components other than the narrow pitch components, and
which are configured to generate heat greater than or equal to a
predetermined amount, the fan (18) configured to blow wind onto the
heat generating component group (16) in order to cool the heat
generating component group (16), and the printed board (12) on
which the narrow pitch component group (14) is mounted in a manner
so that wind is not blown onto the narrow pitch component group
(14) by the fan (18).
In accordance with this feature, with a simple configuration, it is
possible to prevent the wind blown by the fan (18) from flowing to
the narrow pitch component group (14), while also cooling the heat
generating components by the wind blown from the fan (18).
Accordingly, it is possible to prevent the narrow pitch components
from malfunctioning due to the wind blown from the fan (18).
Further, it is possible to prevent an increase in the size of the
motor driving device (10).
The narrow pitch component group (14) may be mounted on the one
surface (12a) of the printed board (12), and the heat generating
component group (16) and the fan (18) may be disposed on a side on
the opposite surface (12b) of the printed board (12) from the one
surface (12a). In accordance with this feature, with a simple
configuration, it is possible to prevent the wind blown by the fan
(18) from flowing to the narrow pitch component group (14), while
also cooling the heat generating components by the wind blown from
the fan (18). Accordingly, it is possible to prevent the narrow
pitch components from malfunctioning due to the wind blown from the
fan (18).
The heat generating component group (16) may be arranged while
being separated at a predetermined distance from the printed board
(12). In accordance with this feature, with a simple configuration,
it is possible to more effectively prevent the wind blown by the
fan (18) from flowing to the narrow pitch component group (14),
while also cooling the heat generating components by the wind blown
from the fan (18). Accordingly, it is possible to more effectively
prevent the narrow pitch components from malfunctioning due to the
wind blown from the fan (18).
The guiding member (19, 30) may be provided, which is configured to
block the wind blown from the fan (18) from flowing to the narrow
pitch component group (14), and to guide the wind blown from the
fan (18) toward the heat generating component group (16). In
accordance with this feature, with a simple configuration, it is
possible to reliably prevent the wind blown by the fan (18) from
flowing to the narrow pitch component group (14), while also
cooling the heat generating components by the wind blown from the
fan (18). Accordingly, it is possible to reliably prevent the
narrow pitch components from malfunctioning due to the wind blown
from the fan (18).
The narrow pitch component group (14) may be arranged at one end
side (right side) in a predetermined direction (left/right
direction) of the printed board (12), and the heat generating
component group (16) may be arranged at another end side (left
side) in the predetermined direction (left/right direction) of the
printed board (12). As viewed in plan, the first region (14a) in
which the narrow pitch component group (14) is arranged, and the
second region (16a) in which the heat generating component group
(16) is arranged, may be separated from each other by a
predetermined interval along the predetermined direction
(left/right direction). As viewed in plan, the fan (18) may be
configured to blow the wind in a direction (front/rear direction)
perpendicular to the predetermined direction (left/right
direction), and thereby to cool the heat generating component group
(16). In accordance with this feature, with a simple configuration,
it is possible to prevent the wind blown by the fan (18) from
flowing to the narrow pitch component group (14), while also
cooling the heat generating components by the wind blown from the
fan (18). Accordingly, it is possible to prevent the narrow pitch
components from malfunctioning due to the wind blown from the fan
(18).
The motor driving device (10) may be configured to drive the motors
of each of respective axes, and the narrow pitch component group
(14), the heat generating component group (16), and the fan (18)
may be provided for each of the motors of the respective axes. In
accordance with this feature, one motor driving device (10) can
drive each of the motors of the respective axes. Further, with a
simple configuration, it is possible to prevent the narrow pitch
component groups (14) of the respective axes from malfunctioning
due to cooling of the heat generating component groups (16) of the
respective axes.
The present invention is not limited to the above described
embodiments. It is a matter of course that various modifications
can be made without departing from the gist of the present
invention.
* * * * *